This invention relates to the packing and shipping, in economical form, of automotive and vehicular pneumatic tire carcasses after manufacture.
It is well known that pneumatic tire carcasses, especially those for tubeless type tires, are created in the form of a stiffened rubber annular having a circular shape with a central hole. The reinforced composite construction of such tire carcasses, creates them in their ultimate inflated shape, even though most of the space contained within the tire is empty air space. The tires are flexible, within limit, but cannot be excessively deformed, crimped or bent without suffering irreversible damage to the internal cord structure, producing carcass weakening and premature failure.
The typical form of shipment of such tires is in the form of a rick, created by stacking alternate rows of tires within a shipping container; each row of tires is placed at a substantially acute angle; successive rows are placed at alternating angles, creating an interleaved and interlocking effect. Such a rick appears from the side as a very large herringbone pattern.
The generally high friction between adjacent tires together with the interlocking effect provided by this herringbone rick construction tends to restrain the tires from shifting, even though the overall density of a tire shipment is quite low because of the enclosed air space. Although the herringbone rick has been determined, through experimentation, to be the most efficent method of packing tires within a rectangular container for shipment, it is a low density packing, and shipment charges remain a considerable portion of the logistics of manufacturing and distributing tires.
Since the shipment of automobile tires within the United States is principally by truck borne trailer, volumetric limits, and not weight are the principal constraint on tire shipment costs and a principal economic contributor to the overall cost of manufacture and sale of tires.